bolts thread infos....please

[giorgio67 185]

Hi guys,

I need your help.

I can't recognize the thread of the three bolts for the gearbox bracket mounting. (the alloy with the 3 bushes)

They seem 12mm x 1,25 but....the hole is smaller than the standard specification for this thread/pitch, so maybe they are imperial or what?

I'm pretty sure that they are not metric.

Many thanks

Ciao Giorgio

....just found them on the part list chassis section.

1/2" UNF.. but I don't know if it is a Coarse, Fine, Extra fine pitch.

Does anyone know the exact pitch of these bolts and where I can find (I don't know the name sorry) the "threaded tool" with the right measure?

Thanks

Giorgio

Edited October 29, 2008 by ghe67

[andydclements 761]

UNF is a thread definition in itself.

United National Fine.

[giorgio67 185]

Thanks Andy....my mistake.

If it is a 1/2 UNF it can be only a fine pitch.

Regards

Giorgio

[naasaa 31]

Am I mistaken here?

I thought that UNC and UNF are american dimension, whereas Withworth is a British standard. And that the angels of the threads are different!

If I want to by an assortment of bolts for a Lotus. Which sizes are the most common?

Thanks

Lars

[andydclements 761]

UNF and UNC do originate from the USA. Whitworth and BSF are British. By angles of the thread I assume you mean the shape of the "tooth" of the thread rather than the angle it moves along the bolt at, and yes they have different patterns.

1/2 UNF are used on quite a few suspension components, but the bolts are different lengths, so getting an assortment to over those would be difficult.

Also keep in mind some people will swap bolts, not just UNF to BSF or UNF to UNC, but 1/2 inch to 12mm, 3/8 to 10mm ect, so the sizes you have on the car may not be the size it was originally designed to have, so the selection would need to be very varied.